1. Field of the Invention
The present invention relates to an on-failure blind stopper system that stops rotation of a rotation shaft when a failure occurs during lifting or lowering of a bottom part of a blind whose shielding member(s) is lifted or lowered by that a lifting/lowering cord lifts or lowers the bottom part.
2. Description of the Related Art
A known conventional on-failure blind stopper system of this kind is described in Japanese Utility Model Publication No. H3-51516. In this publication, a roller for guiding a lifting/lowering cord is disposed at an opening in a side plate of a support main unit for supporting a take-up drum, and a claw is disposed in the support main unit. The claw has a contact member adapted to abut against the lifting/lowering cord on one side thereof, and is pivoted at one end thereof, and is urged upward at the other end thereof by a spring so that the claw can abut against a ratchet wheel. If a shielding member of the blind bumps against an obstacle, the lifting/lowering cord sags, and the pressing force from the lifting/lowering cord on the contact member is removed. Thus, the claw rotates about the pivot point to engage with the ratchet wheel, thereby stopping the rotation of the take-up drum and stopping the movement of the lifting/lowering cord.